David Karl Krusen (born March 10, 1966) is an American musician who is best known for being the original drummer for the American rock band Pearl Jam and for his work on the band's debut album, Ten. Krusen was also a member of the bands Hovercraft, Candlebox, and Unified Theory.

Krusen was recruited in 1990 by bassist Jeff Ament and guitarist Stone Gossard to be the drummer for Pearl Jam. Krusen was asked to join Pearl Jam after auditioning with the band.[5] Krusen was a member of the band from its first official show on October 22, 1990, to the completion of the band's debut album, Ten in 1991. After the recording sessions for Ten were completed, Krusen left Pearl Jam in May 1991 and checked himself into rehabilitation.[5] According to Krusen, he was suffering from personal problems at the time.[5] Krusen said, "It was a great experience. I felt from the beginning of that band that it was something special," and added, "They had to let me go. I couldn't stop drinking, and it was causing problems. They gave me many chances, but I couldn't get it together."[4] Vocalist Eddie Vedder said, "Krusen was a real hero...He was going through a lot, but he had something really special."[6]

In the mid-1990s, Krusen joined Beth Liebling and Ryan Shinn in the band Hovercraft under the stage name "Karl 3‒30". Krusen replaced previous drummer Eddie Vedder. With a more technically proficient drummer, the band was now free to play beyond the lo-fidelity noise experiments of its debut release, and play proper shows with structured improvisation and avant experimentalism. While as a member of Hovercraft, Krusen toured with the band and recorded the album Akathisia (1997).

In 1994 Krusen co-founded Diamond Star Halo with former Candlebox bass player Aaron Seravo. The two were introduced by a mutual friend and discovered they had exactly the same vision for a band. The band was completed by Singer Bo Bligh and bassist Steve Martin the band released their first record in 1995 tilted In The Rough on Regal Recordings. The album was produced by Cristopher Thorne of Blind Melon and Kevin Martin of Candlebox & was mixed by Kelly Grey. The band enjoyed moderate success but not to the level of their former bands Candlebox and Pearl Jam. After much conflict centering around singer Bo Bligh's drug addictions the band dissolved. There was a later version of the band reformed by Seravo in 2000. Aaron Seravo died of cancer January 9, 2011, surrounded by friends and loved ones, at Stanford University Hospital. Steve Martin died very early in 2011 as well (committing suicide) a few days before Seravo's passing.

Krusen played drums with the band Unified Theory on its self-titled album, issued in August 2000. The band was made up of two ex-Blind Melon members (bassist Brad Smith and guitarist Christopher Thorn) and newcomer Chris Shinn on vocals/guitar. Unified Theory began to form in early 1998. After the first plan to carry on Blind Melon with a new singer didn't work out, Smith and Thorn decided to start a new band and came across vocalist Chris Shinn after moving to Los Angeles, California. Krusen was already friends with Thorn and Smith. While working on tracks for a second album, delays set the band back, and Krusen grew somewhat frustrated and left. This eventually led to Unified Theory's break-up.

After leaving Pearl Jam, Krusen teamed up with former Son of Man vocalist Tal Goettling, bass player Matt McClinton, and guitarist Tim Bethune to form the short-lived but highly acclaimed Purple Decade. The band recorded two demo tapes before imploding under the pressures of the Seattle and Los Angeles music scenes. In 2004, Krusen performed with musician Shawn Snyder as part of his backing band. He was a part of a Seattle, Washington-based band called Novatone which released the album Time Can't Wait in 2005. He was Cheyenne Kimball's drummer from 2005 to 2007 and played on her debut album, The Day Has Come (2006). He is currently working on a blues/noise-groove, avant-garde record and performing live and in the studio with various artists including Martyr Reef, Toy Robot, George Stanford, Lowlight, Jesse Cole, Foster Timms, Matthias Sturm, La La Birdtime, Shelby, Carolyna Loveless, Chris Robinson, Puppies and Kittens and John Pringle. He is now touring with Ida Maria and recording her third album due out in 2012.